1. Field of the Invention
This invention generally relates to concrete forming systems, and more particularly, to an improved system for forming changes in elevations in concrete slabs.
2. Description of the Prior Art
In large and other size buildings, such as apartments, offices, R&D facilities, and the like, changes in elevations to concrete floors are usually made using wooden or metal forms. These forms are normally secured in place and both the forms and securing elements are removed after the concrete sets.
Many problems occur because of the use of these known forms, their securing elements, and the removal thereof.
To overcome problems with the known forms, various types of metal concrete forming systems have been devised. In particular, U.S. Pat. No. 4,443,981 to Weiss, discloses a metal concrete forming system in which the form remains in place after the concrete is poured. The system consists of longitudinal rails connected to stakes and includes clips which fit snugly and securely together over angled portions of the rails to hold a number of elongated rails together. In addition, a corner holder is provided to secure two perpendicular rails together to complete a form. However, because of the shape of the rails and the use of the stakes, this type of a forming system could not be used in buildings where changes in elevations are needed.
Other devices are known which show different constructions of metal forms and brackets or braces. However, none of the known devices contain the specific structural form, braces and holding members of the present invention, nor are they for use in forming changes in elevation in poured concrete surfaces. Therefore, there exists a need in the art for an improved method and system for forming changes in elevations in poured concrete surfaces.